Printer including an ink cartridge

ABSTRACT

An ink jet printer including a cartridge which moves along a print area, a head mounted on the carriage, an ink cartridge mounted on the cartridge for supplying ink to the head, a lever on the carriage for mounting or demounting the ink cartridge with respect to the carriage and a stopper for stopping the movement of the carriage by coming into contact with the lever when an operation of mounting the ink cartridge by the lever has not been completely effected. The ink jet printer may also include a resilient member for supporting the ink cartridge on the carriage.

This is a continuation of application Ser. No. 08/464,036, nowabandoned, filed on Jun. 5, 1995 for PRINTER INCLUDING AN INK CARTRIDGE,which was a divisional application of application Ser. No. 08/119,012,now U.S. Pat. No. 5,648,807, filed on Sep. 9, 1993.

BACKGROUND OF THE INVENTION

The present invention relates generally to printers, and, in particular,to improvements in an automatic-paper-feeder portion of a printer havingan automatic paper feed incorporated therein.

Further, the present invention relates to improvements in a drivingmechanism for individually feeding sheets of paper.

Still further, the present invention relates to improvements in ink jetprinters, and specifically to improvements in the construction andarrangement of the print area thereof, to improvements in theconstruction of the mounting the ink cartridge on the carriage thereof,and to improvements for reducing the width of ink jet printers in thedirection of a row.

Further, the present invention relates generally to a method ofdischarging paper in an ink jet printer, and in particular, to animproved technique of the discharging paper in which the dischargedpaper is neither damaged nor smeared.

FIG. 56 depicts a conventional printer described in Japanese UtilityModel Unexamined Publication No. 272952/1991. An automatic paper feederis constructed and arranged having a paper feed cassette 2002, which isa paper stacker, detachably mounted in a printer body 2001 so a deadspace DS is formed between the bottom of paper feed cassette 2002 andthe bottom of body 2001.

FIGS. 57-59 depict a second conventional printer described in JapanesePatent Utility Model Publication No. 74825/1988 having a stacker section2004 on which paper P is stacked, incorporated in a printer case 2003constructed and arranged so a dead space DS is formed between the bottomof printer case 2003 and stacker section 2004.

As illustrated above, it is difficult to make the printers compactbecause of the dead space within the printer casings.

In the conventional printer construction of FIGS. 57-59, the stackersection is arranged as follows. If a paper discharge support 2101rotates in a counterclockwise direction as viewed in FIGS. 58 and 59, anoperating arm 2102 rotates therewith causing an intermediate lever 2103to rotate in the clockwise direction as viewed in FIGS. 58 and 59. Anengaging lever 2104 is rotated in said counterclockwise direction by therotation of intermediate lever 2103, and a pressure-plate operatinglever 2106 rotates in the same direction as engaging lever 2104 sincethey are both mounted for rotation with lever shaft 2105. A pressureplate member 2107 moves downward as viewed in FIG. 57 by the rotation ofpressure-plate operating lever 2106 to allow paper P to be insertedbetween pressure plate member 2107 and a separation pawl 2108, therebymaking it possible to accommodate paper P in a feeding holder 2109.

However, in such a conventional printer, if paper discharge support 2101rotates in the counterclockwise direction, pressure plate member 2107moves downward, but separation pawl 2108 does not move. Therefore, if aplurality of sheets of paper are inserted, the edges of the top sheetsmay enter above separation pawl 2108. Hence, this printer constructionhas a problem with the feeding-in operation.

In the above construction, intermediate lever 2103 and engaging lever2104 are necessary, resulting in a complicated printer construction.

FIG. 60 depicts a mechanism for driving a paper feed-in roller in aconventional printer described in Japanese Utility Model UnexaminedPublication No. 184174/1989. In FIG. 60, a transmission arm 2502 issupposed on an apparatus body and can rotate about a fulcrum 2501. Adrive gear 2503 is axially supported on fulcrum 2501. Further, atransmission gear 2505 for transmitting rotation from drive gear 2503 toa roller gear 2504 is axially supported at one side of transmission arm2502. As a left end 2502′ of transmission arm 2502 is pressed down bythe movement of a carriage (not shown) against a return spring 2506,transmission gear 2505 engages roller gear 2504, and drives a paperfeed-in roller (not shown) fixed on shaft 2507, which also rotatablysupports roller gear 2504.

The conventional mechanism employing the structures described above hasthe following problem.

Since transmission arm 2502 is not resilient, if left end 2502′ oftransmission arm 2502 is pressed too hard by the carriage, the force oftransmission gear 2505 against roller gear 2504 is too much, and gear2504 and 2505 will not rotate smoothly.

FIGS. 61-63 depict a conventional ink jet printer described in JapaneseUtility Model Unexamined Publication No. 1101980/1991. Described in anink jet head 2201 and a paper feed roller 2202 for feeding paper P to aprint area 2201a where printing is performed. A transport roller 2203,roller 2202 which is disposed downstream of paper feed roller 2202relative to print area 2201a, rotates at a higher peripheral speed thanpaper feed roller 2202 and pulls paper P past paper feed roller 2202. Apaper holding plate 2204 holds paper P against paper feed roller 2202.In a printer having the above construction, paper P is printed in printarea 2201a while paper P floats.

However, with this type of printer, “blind striking” may occur in whichink is ejected from ink jet head 2201 despite the fact there is no paperP in print area 2201 a.

Blind striking occurs after the paper is detected by a paper detectingsensor disposed upstream of the print area but the paper fails to reachthe print area due to a failure in paper feed, or the like. If the paperis detected by the paper detecting sensor, ink jet head 2201 operates onthe assumption that the paper is present in the print area.

As shown in FIGS. 61-63, because there is nothing interposed between inkjet head 2201 and paper feed roller 2202, when “blind striking” occurs,the ink ejected from ink jet head 2201 adheres to paper feed roller2202, thereby staining later sheets of paper P. This has been a seriousproblem with conventional printers having this construction.

Furthermore, a distal end of paper holding plate 2204 in theconventional printer shown in FIGS. 61-63 functions to restrict theprinting surface of the paper P. As noted above, in this conventionalprinter paper holding plate 2204 presses paper P paper feed roller 2202.However, with inherent surface irregularities in paper feed roller 2202,paper holding plate 2204 is pivotably displaced due to the effect ofthese irregularities and the pressure exerted on paper P by paperholding plate 2204 varies. This results in the gap between the printingsurface and ink jet head 2201 varying, which adversely affects the printquality. In addition, since a plurality of paper holding plates 2204 areprovided in the axial direction of paper feed roller 2202, as shown inFIG. 61, paper holding plate 2204 are affected by the surfaceirregularities of paper feed roller 2202 at different locations in theaxial direction thereof, and will pivot at different angles and atdifferent instances, which will also adversely affect the print quality.

Further, ink jet printers print by discharging ink onto paper. If theprinted paper is discharged by means of, for instance, a pair of rubberrollers, the ink that is not dry will adhere to the rubber rollers onthe printed surface side, thereby smearing the ink on the printedsurface of the paper.

Accordingly, FIG. 64 illustrates an ink jet printer described inJapanese Utility Model Unexamined Publication No. 41277/1990 that hasbeen proposed to overcome this problem. Paper P1, printed on by an inkjet head H, is discharged using a paper discharge roller 2401 made of aresilient material, such as rubber, and a plurality of star wheels 2402which rotate with the paper nipped between star wheels 2402 and paperdischarge roller 2401. Star wheels 2402 are urged toward paper dischargeroller 2401 by means of respective shafts 2403 each having a resiliencyor spring characteristic.

However, the conventional printer employing the structure describedabove has the following problem.

Star wheels 2402 are urged toward paper discharge roller 2401 by shafts2403 each having a spring characteristic. If there are variations in thespring characteristic (i.e., on the urging force) of shafts 2403, thevariations appear directly as variations in the pressing force of starwheels 2402 upon paper discharge roller 2401.

If the pressing force of star wheel 2402 upon paper discharge roller2401 is small, it becomes impossible to obtain a transporting force forthe paper. Conversely, if the pressing force is too large, perforationscan form in the paper, and the printed surface, therefore, is liable tobe damaged.

Since the ink jet printer prints onto paper by the ejection of ink, whenprinting is performed continuously on a plurality of sheets of paper, asubsequent sheet of paper may be discharged before the ink on theprinted paper dries. If the subsequent sheet of paper contacts thepreceding sheet of paper, the ink on the printed surface will smear.

Japanese Utility Model Unexamined Publication No. 134865/1992 describesa discharged paper stacker that overcomes this problem. The constructionthereof is described with reference to FIGS. 65-68. FIG. 65 illustratesa discharged-paper tray 2306 having a V-shape or concave shape. FIG. 66shows how printed sheets of paper P1 are stacked in the concave shapethereby delaying the time until subsequently discharged paper P2contacts printer paper P1. In addition, FIG. 67 illustrates a techniquein which paper P2 is discharged and is set in a convex shape to delaythe time until paper P2 slidably contacts printed paper P1. In thisarrangement, central interior roller 2304′ is of a larger diameter thanouter interior rollers 2304 while central exterior roller 2305′ is ofsmaller diameter than outer exterior rollers 2305. Furthermore, FIG. 68describes a technique in which paper P2 is discharged and is set in acorrugated shape to further delay the time until paper P2 contactsprinted paper P1. In this construction, interior rollers 2304″ haveprojecting peripheral hubs while exterior rollers 2305″ are thin andaligned with the central region of interior rollers 2304″ between thehubs.

However, these conventional techniques employing the structuresdescribed above have the following problems.

First, even if discharged-paper tray 2306 is formed in a concave shape,if paper P1 is very stiff, paper P1 will not conform and stack in thedesired concave shape. As a result, the time until subsequentlydischarged paper P2 slidably contacts printed paper P1 is not delayed,and the printed surface of printed paper P1 will smear. Also, becausethe shape of discharged-paper tray 2306 is concave, the space occupiedby discharged-paper tray is larger than desired.

Furthermore, the print quality utilizing the techniques shown in FIGS.67 and 68 is poor. Paper discharge rollers 2304 and 2305 cause paper P2to be set directly in the convex shape or in the corrugated shape. Thisresults in paper P2 retaining the aforesaid shapes while in the printingsection, thereby adversely affecting the print quality.

Ink jet printers having an ink cartridge mounted on a carriage haveheretofore been proposed. These printers are more compact than a printernot having the ink cartridge mounted on the carriage and where ink issupplied to the ink jet head located above the carriage through a pipefrom an ink tank.

Japanese Utility Model Unexamined Publication No. 101949/1991 describesa printer in which the operation of mounting or demounting of the inkcartridge with respect to the carriage can be performed simply by theoperation of a lever.

However, this type of conventional printer is constructed and arrangedso that the carriage can reciprocate even in a case where the operationof mounting the ink cartridge has not been performed completely.

For this reason, in the event that the carriage reciprocates in thestate in which the mounting of the ink cartridge has been performedincompletely, there is the possibility of the ink cartridge coming offthe carriage, thereby possibly staining paper or the path of the paperin the printer.

In addition, since no shock-absorbing member is interposed between thecarriage and the ink cartridge, when the carriage suddenly reversesdirection, any inertial force of the ink carriage is directlytransmitted to the cartridge, causing vibrations to the carriage andexcess noise.

Ink jet printers generally have a print area where printing is performedon recording paper by the head mounted on the carriage whichreciprocates in the direction of a row, and a nonprint area locatedoutside the print area where printing is not performed. In such ink jetprinters, if printing is not performed for a predetermined time, the inkat the tip of the nozzle of the head becomes dry, and cause the nozzleto clog. To prevent this, it is necessary to perform a so-called“capping” operation and cover the ink jet head with a cap. However, ifclogging has occurred, it is necessary to clear the ink path by forciblysucking the ink from the nozzle using a sucking mechanism. The cappingand sucking operations are performed when the carriage is in thenonprint area. Further, when the printing operation is continuouslyperformed, the paper is fed for the portion of the interlinear spacewhen the carriage is in the print area.

The driving for paper feed and the driving of the suction mechanism areconventionally performed by separate drive motors although printers inwhich the driving of the respective mechanisms is performed by one drivemotor have become popular in recent years.

FIGS. 69-71 are schematic diagrams respectively illustrating the printarea and the nonprint area in different types of conventional ink jetprinters with the frame of the printer indicated as F.

FIG. 69 describes an ink jet printer having nonprint areas a1 and a2 onboth sides of a print area P. When the carriage is in nonprint area a1,the paper feeding-in operation and the paper feeding operation areperformed. When the carriage is in nonprint area a2, the cappingoperation is performed. Also, when the carriage is in nonprint area a2,the paper feeding operation and the suction operation are performedsimultaneously.

FIG. 70 describes an ink jet printer having three nonprint areas a1, a2,and a3 on one side of print area P. When the carriage is in print area Pand a first nonprint area a1, the paper feeding operation is performed.When the carriage is in nonprint area a2, the paper feeding-in operationis performed. When the carriage is in nonprint area a3, the suctionoperation is performed. In addition, the capping operation is performedwhen the carriage is in any one of the nonprint areas a1, a2, and a3.

Similarly, the ink jet printer shown in FIG. 71 has three nonprint areasa1, a2, and a3 on one side of the print area P. When the carriage is inthe first nonprint area a1, the paper feeding-in operation is performed.When the carriage is in nonprint area a2, the paper dischargingoperation is performed. When the carriage is in nonprint area a3, thesuction operation is performed. In addition, the paper feeding operationis performed when the carriage is in any one of the nonprint areas a1,a2, and a3.

The conventional ink jet printers employing the structures describedabove have the following problems.

As illustrated in FIG. 69, only two nonprint areas are provided for theink printer so the width of the printer in the direction of the row canbe made small. Nevertheless, since both the paper feeding operation andthe suction operation are performed simultaneously in nonprint area a2,a problem arises when the recording paper is continuously fed during thesuction operation. Particularly, in a case where the recording paper iscontinuous-form paper, the recording paper is fed by the portion inwhich the suction operation was performed, which is very inconvenient.In addition, if the paper feeding operation is performed in a state inwhich capping is provided, the suction operation is performed even ifthe head is not clogged, resulting in wasted ink.

The ink jet printer shown in FIG. 70 does not have the above-mentionedproblems, but, since there are as many as three nonprint areas, thewidth of the printer in the direction of the row becomes large.

The ink jet printer shown in FIG. 71 is also provided with threenonprint areas, so the width of the printer in the direction of the rowis large. Moreover, since both the paper feeding operation and thesuction operation are performed simultaneously in nonprint area a3, aproblem similar to that of the printer shown in FIG. 69 will result.

By the arrangement in accordance with the invention, the foregoingdeficiencies in the prior art are overcome. Specifically, a compactprinter is provided. The printer paper feed mechanism permits anaccurate feed-in operation with a simple mechanism which prevents thepaper's insertion above the separation pawl. Further, the smoothoperation of the mechanism for driving the feed-in roller is assured.The ink jet printer in accordance with the invention is designed so thatthe paper is not stained even if blind striking occurs and to keepconstant the gap between the printing surface of the paper and the head.Further, the ink jet printer transports paper readily without stainingthe printed surface by, at least in part, delaying the time until paperwhich is discharged next is brought into sliding contact with theprinted paper, while preventing the configuration of the paper fromaffecting the printing section. Still further, means is provided toprevent the ink cartridge from coming off the carriage. The cartridgemounting mechanism is adapted to reduce vibration and noise. Stillfurther, the width in the direction of the row for ink jet printer isreduced while the paper feeding and suction operations are selectivelyeffected.

SUMMARY OF THE INVENTION

Generally speaking, in accordance with the invention, a printer inaccordance with one aspect of the present invention includes anautomatic paper feeder having a stacker section capable of setting aplurality of sheets of paper therein, wherein a bottom of said stackersection is formed by a bottom itself of a printer case.

The printer in accordance with another aspect of the present inventionincludes a stacker section capable of setting a plurality of sheets ofpaper therein; a hopper disposed in said stacker section to urge thepaper upwardly; a pair of swinging members each having a separationpawl-located above a corner of a leading end of the paper and apressing-down portion for pressing down said hopper, each of saidswinging members being supported swingably about a shaft located betweensaid separation pawl and said pressing-down portion; and an operationlever having a pair of actuating portions capable of pressing downwardsaid swinging members, said operation lever being supported rotatablyabove said stacker section.

The printer in accordance with still another aspect of the presentinvention includes a feed-in roller for feeding sheets of paper one byone; a carriage for printing the sheet fed by said feed-in roller; afeed-in gear for rotating said feed-in roller; and a movable gearsupported rotatably by a rotatable lever and capable of assuming a firstposition in which said movable gear meshes with said feed-in gear torotate said feed-in gear and a second position in which said movablegear does not mesh with said feed-in gear, wherein a spring memberhaving one end supported by said lever and another end supported by aframe of said printer, and an actuating portion is provided on saidcarriage to rotate said lever toward the first position in which saidmovable gear meshes with said feed-in gear by pressing and displacing anintermediate portion of said spring member.

The ink jet printer in accordance with a further aspect of the presentinvention includes a feed roller for feeding paper to a print area whereprinting is effected by an ink jet head; a transport roller disposeddownstream of said feed roller relative to the print area to transportthe paper in such a manner as to stretch the paper between the transportroller and said feed roller by rotating the transport roller at aperipheral speed faster than that of said feed roller; and an inkshielding portion disposed so as to form a passage of the paper betweenthe same and said ink jet head over the entire print area.

The ink jet printer in accordance with a still further aspect of thepresent invention includes a feed roller for feeding paper to a printarea where printing is effected by an ink jet head; a transport rollerdisposed downstream of said feed roller relative to the print area totransport the paper in such a manner as to stretch the paper between thetransport roller and said feed roller by rotating the transport rollerat a peripheral speed faster than that of said feed roller; and apressing member for pressing the paper over an entire widthwise lengththereof, a pressing portion of said pressing member being disposed at aposition between said feed roller and said transport roller and wheresaid pressing portion is in contact with neither of said two rollers.

In accordance with a further aspect of the present invention, there isprovided an ink jet printer for discharging paper printed by a printingsection having an ink jet head, by means of a plurality of paperdischarging rollers and a plurality of star wheels each of which rotateswhile nipping the paper between the same and said paper dischargeroller, said ink jet printer including a shaft for supporting two starwheels as a unit at opposite ends of said shaft; and an urging memberfor urging a central portion of said shaft toward said paper dischargerollers.

In accordance with a further aspect of the present invention, there isprovided a method of discharging paper characterized in that the paperprinted by a printing section having an ink jet head is discharged whileforcibly urging the paper in a concave shape in which a printed surfaceis rendered concave as viewed in a discharging direction.

In accordance with a further aspect of the present invention, the methodof discharging paper includes the steps of transporting the paperprinted by a printing section having an ink jet head in a flat state asviewed in a discharging direction; and discharging the paper whileforcibly urging the paper into a concave shape in which a printedsurface is rendered concave as viewed in the discharging direction.

The ink jet printer in accordance with a further aspect of the presentinvention includes a pair of both-side supporting portions forsupporting from below both side portions of the paper which has beendischarged after being printed on an upper surface thereof by a printingsection having an ink jet head, and a pushing-down portion for pushingdown a central portion of the paper.

In accordance with a further aspect of the present invention, there isprovided an ink jet printer including a carriage which moves along aprint area; a head mounted on said carriage; an ink cartridge mounted onsaid carriage for supplying ink to said head; and a lever provided onsaid carriage for mounting or demounting said ink cartridge with respectto said carriage, wherein a stopper is provided for stopping themovement of said carriage by coming into contact with said lever when anoperation of mounting said ink cartridge by means of said lever has notbeen effected completely.

In accordance with a further aspect of the present invention, there isprovided an ink jet printer including a carriage which moves along aprint area; a head mounted on said carriage; and an ink cartridgemounted on said carriage for supplying ink to said head; wherein saidink cartridge is supported on said carriage through a resilient memberin a direction of movement of said carriage.

In accordance with a further aspect of the present invention, there isprovided an ink jet printer having a print area where the printing ofrecording paper is effected by a head mounted on a carriagereciprocating in a direction of a row and a nonprint area which islocated on both sides of the print area and where the printing by thehead is not effected, said ink jet printer including a drive gearcapable of assuming a paper-feed driving position which is located inone of the nonprint areas for driving a paper feeding mechanism forfeeding the recording paper in a direction essentially perpendicular tothe direction of the row and a suction driving position for driving asuction mechanism for sucking ink from said head; changeover meansdisposed on said carriage for changing over a position of said drivegear; and selecting means located in another one of said nonprint areasfor selecting a state of said changeover means when said carriage enterssaid area.

Accordingly, an object of the present invention is to provide a printerwhich can be made compact.

Another object of the present invention is to provide a printer whichpermits an accurate feeding-in operation with a simple mechanism bypreventing the paper, which is inserted and set in an automatic paperfeeder, from entering above the separation pawl.

Still another object of the present invention is to facilitate thesetting of the paper.

A further object of the present invention is to provide a printer whichmakes it possible to positively ensure the smooth operation of themechanism for driving the feed-in roller.

A still further object of the present invention is to provide an ink jetprinter which will not stain the paper even if blind striking occurs.

An additional object of the present invention is to provide an ink jetprinter which is capable of keeping constant the gap between theprinting surface of the paper and the head.

Still another object of the present invention is to provide an ink jetprinter which is capable of transporting the paper reliably withoutstaining the printed surface.

A further object of the present invention is to prevent the printedsurface of the printed paper from becoming stained by reliably delayingthe time until paper which is discharged next is brought into slidingcontact with the printed paper.

A still further object of the present invention is to prevent theconfiguration of the paper from affecting the printing section.

Still another object of the present invention is to prevent the inkcartridge form coming off an ink jet printer of the type in which theoperation of mounting or demounting of the ink cartridge is effected bythe operation of a lever.

A still further object of the present invention is to reduce thevibrations and the reversing noise caused by the cartridge in thecarriage.

A further object of the present invention is to provide a printer whichis of reduced width in the direction of the row and to selectivelyeffect the paper feeding operation and the suction operation.

Still a further object of the present invention is to provide animproved method of discharging paper in an ink jet printer.

Another object of the present invention is to provide an improved methodof discharging paper that delays the contact of the discharged paperwith the paper previously discharged.

Yet a further object of the present invention is to provide an improvedmethod of discharging paper so the discharged paper does not becomedamaged during the printing and discharging operations.

Still other objects and advantages of the invention will in part beobvious and will in part be apparent from the specification.

The invention accordingly comprises the several steps and the relationof one or more of such steps with respect to each of the others, and theapparatus embodying features of construction, combinations of elementsand arrangement of parts which are adapted to effect such steps, all asexemplified in the following detailed disclosure, and the scope of theinvention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the invention, reference is had to thefollowing description taken in connection with the accompanyingdrawings, in which:

FIG. 1 is a front elevational view illustrating a first embodiment of aprinter in accordance with the present invention;

FIG. 2 is a top plan view of the printer of FIG. 1 in accordance with afirst embodiment of the invention;

FIG. 3A is a cross-sectional view of the left-hand side of a printer inaccordance with a first embodiment of the invention;

FIG. 3B is a rear view of FIG. 3A;

FIG. 4 is an enlarged fragmentary cross-sectional view of the left-handside of a printer in accordance with a first embodiment of theinvention;

FIG. 5 is plan view of a lower case of a printer in accordance with afirst embodiment of the invention;

FIG. 6 is an enlarged fragmentary plan view of the lower case of aprinter in accordance with a first embodiment of the invention;

FIGS. 7(a)-7(c) illustrate a left-side holder, FIG. 7(a) being a planview, FIG. 7(b) being a front elevational view and FIG. 7(c) being across-sectional view taken along line 7c—7c in FIG. 7(a);

FIGS. 8(a)-8(c) illustrate a swinging member, FIG. 8(a) being a planview, FIG. 8(b) being a front elevational view, and FIG. 8(c) being abottom view;

FIGS. 9(a)-(c) illustrate an operation lever, FIG. 9(a) being across-sectional view taken along lines 9a—9a in

FIG. 9(b), FIG. 9(b) being a plan view, and FIG. 9(c) being a left-handside elevational view;

FIG. 10 is a top plan view of the printer in which the upper case isremoved;

FIG. 11 is a fragmentary cross-sectional view taken along line 11—11 inFIG. 10;

FIG. 12 is an enlarged fragmentary sectional view illustrating theoperation of the invention;

FIG. 13 is a cross-sectional view of the printer illustrating theoperation of the invention;

FIGS. 14-16 are fragmentary views sequentially illustrating theoperation of the invention;

FIG. 17 is a development view of a driving system;

FIG. 18 is an enlarged side elevational view of a portion of the drivingsystem of FIG. 17;

FIG. 19 is a left-hand side elevational view of a left-side frame;

FIG. 20 is a cross-sectional view taken along line 20—20 in FIG. 19;

FIGS. 21(a) to 21(g) illustrate an arm, FIG. 21(a) being a left-handside elevational view; FIG. 21(b) being a right-hand side elevationalview; FIG. 21(c) being a plan view; FIG. 21(d) being a cross-sectionalview taken along lines 21d—21d in FIG. 21(a); FIG. 21(e)-being across-sectional view taken along lines 21e—21e in FIG. 21(a); FIG. 21(f)being a cross-sectional view taken along lines 21f—21f in FIG. 21(b);and FIG. 21(g) being a cross-sectional view taken along lines 21g—21g inFIG. 21(b);

FIGS. 22(a) and (b) illustrate a spring member, FIG. 22(a) being a planview, and FIG. 22(b) being a fragmentary front elevational view;

FIG. 23 is a partially cutaway plan view of a carriage;

FIG. 24 is a side elevational view of a printer in accordance with theinvention illustrating the operation thereof;

FIG. 25 is a flow chart explaining the operation of the printer;

FIG. 26 is a schematic diagram illustrating a lever-actuating mechanismusing a spring member;

FIGS. 27 and 28 are partial enlarged sectional side elevational views ofthe print area of the printer showing the operation thereof;

FIG. 29 is a fragmentary enlarged sectional side elevational view of theprint area;

FIG. 30 is a fragmentary enlarged front plan view of the print area;

FIG. 31 is a partial enlarged sectional side elevational view of thepaper discharge section of the printer;

FIG. 32 is a perspective view of a pushing-down portion;

FIGS. 33-36 are perspective views of the discharge section illustratingthe operation of the printer;

FIG. 37 is a plan view illustrating the carriage in a state in which theink cartridge is not measured;

FIG. 38 is a cross-sectional view taken along line 38—38 in FIG. 37;

FIG. 39 is a cross-sectional view illustrating the carriage in a statein which the ink cartridge is mounted;

FIG. 40 is a perspective view of a lever;

FIG. 41 is a cross-sectional view taken along line C—C in FIG. 40;

FIG. 42 is a diagram illustrating the operation of the lever;

FIG. 43 is a fragmentary front elevational view, partly in section, ofthe printer at a carriage stop position;

FIGS. 44-45 are partial cross-sectional views of a right-hand side ofthe printer and illustrating the operation of a stopper;

FIG. 46 is a schematic diagram illustrating the print area and nonprintareas in accordance with a second embodiment of the ink jet printer inaccordance with the present invention;

FIG. 47 is a fragmentary front elevational view illustrating a portionof the internal structure of the embodiment;

FIG. 48 is an enlarged front elevational view of a second nonprint areaA2;

FIG. 49 is a right-hand side elevational view thereof;

FIG. 50 is a plan view thereof;

FIG. 51 is a perspective view thereof, as seen from the rear side, withthe frame omitted;

FIG. 52 is an enlarged front elevational view of a first nonprint areaA1;

FIG. 53 is a plan view thereof;

FIG. 54 is a perspective view of a portion thereof;

FIG. 55 is a fragmentary perspective view illustrating the operationthereof; and

FIGS. 56 to 71 show printers and portions thereof in accordance withprior conventional art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A brief overview of the printer in accordance with the invention willfirst be given with reference to FIGS. 3A and 3B.

FIG. 3A of the drawings illustrates an automatic paper feeder, generallyindicated at 210, which includes an automatic feeding path 202 and afirst lever 921 for detecting the paper fed to automatic feeding path202. FIG. 3B is a rear view of FIG. 3A. A gate roller 340 is driven inpressure contact with a paper feed roller 330. Also, a pinch roller 350is driven in pressure contact with paper feed roller 330. A carriage 60has an ink cartridge 90 mounted thereon. A transport section, generallyindicated at 380, is disposed in a paper discharging path 470. Dischargesection 490 discharges the paper while holding the paper in a concaveshape while seen in a transporting direction. An operation lever 260also serves as a discharged-paper tray. An intermediate frame 110 has anink shielding portion 112 and a pressing member 140.

The sheets of paper P are fed one by one to automatic feeding path 202by the operation of a paper feed-in roller 312 which will be describedlater in detail.

The paper which has been fed in causes first lever 921 to rotatecounterclockwise as viewed in FIGS. 3A, 3B about a shaft 921a. Therotation of first lever 921 causes a second lever 922, also for paperdetection, to rotate counterclockwise as viewed in FIG. 3. Furthermore,as a third lever 922b is similarly rotated counterclockwise, a paperdetection switch 923 detects the feeding of the paper.

The detected paper, after being subjected to deskewing as will bedescribed later, is wound around paper feed rollers 330, and reachesprint area PA via pinch roller 350.

Pinch roller 350 is rotatably attached to a distal end of a paper guide53 suspended from a rear frame 130 by means of a spring 52 so that paperguide 53 rotates about a fulcrum 51.

Print area PA is formed between an upper surface of intermediate frame110 and an ink jet head H attached to carriage 60. Carriage 60reciprocates in a direction perpendicular to the plane of the drawing ofFIG. 3A. A guide shaft 163 guides one end of carriage 60. The other endof carriage 60 is guided by an upper frame 120.

The paper printed on in print area PA passes through transport section380 and is discharged onto discharged-paper tray 260 via dischargesection 490 which includes pushing-up portions 491, 491 for pushing upboth sides of the paper, and a knurled roller 492 for pushing down acentral portion of the paper.

The above-described operation from feeding to discharging iscontinuously performed in cases where printing is performed on aplurality of sheets of paper. The sheets are fed one by one by automaticpaper feeder 210, and the printed sheets of paper P1 are consecutivelystacked on discharged-paper tray 260.

Next, a detailed description will be given to each section of theprinter.

As shown in FIGS. 3A, 3B and 4, automatic paper feeder 210 includes astacker section, generally indicated at 220, a hopper 230, a pair ofswinging member 240, 250 (only 240 is shown), the aforementionedoperation lever 260, and paper feed-in roller 312.

Also, as shown in FIGS. 5 and 6, stacker section 220 includes a bottom221 of a lower case 11 of the printer, aligning members 222, 222 foraligning the tips of the sheets of paper and formed integrally with andprojecting upwardly from bottom 221, a right-side holder 223 for holdingthe right sides of the sheets and similarly formed integrally with andprojecting upwardly from bottom 221, and a left-side holder 225 forholding the left sides of the sheets and fixed to bottom 221 by a screw224. Left-side holder 225 is further illustrated in FIGS. 7(a)-7(c).Left-side holder 225 is not formed integrally with the case so it ispossible to change the position of or replace left-side holder 225.

A loop holder 223a for the paper and a support shaft 223b of swingingmember 240 are formed integrally on right-side holder 223. FIGS. 7(a) to7(c) further disclose a hoop holder 225a and a support shaft 225b of aswinging member 250 formed integrally on left-side holder 225.

In addition, as shown in FIGS. 5, 6 and 7(a) to 7(c), a right-side loopcanceling wall 228 is formed integrally on bottom 221 of the case, whilea left-side loop canceling wall 225c is formed on the left-side holder225.

FIGS. 4 and 6 show hopper 230 formed by an iron blank in the form of asheet having inserting portions 231, 231 formed integrally and insertedinto support holes 226 formed in the bottom 221 of the aforementionedcase. Hopper 230 is also formed integrally with receiving portions 232,232 with respect to the swinging members, as shown in FIGS. 4 and 6. Asinserting portions 231, 231 are inserted into support holes 226 in thebottom of the case, the hopper 230 is rotatably mounted in stackersection 220. In each support hole 226, a tongue 226a for resilientlysupporting inserting portion 231, is integrally formed with bottom 221,as shown in FIGS. 5 and 6. A compression spring 233 is provided betweenbottom 221 and hopper 230. Hopper 230 is urged toward paper feed-inroller 312 by the action of compression spring 223.

As shown in FIGS. 4, 6 and 8(a) to 8(b), swinging member 240 has aseparation pawl 241 located above, a corner Pd (see FIG. 6) of a leadingend of the paper as well as a pressing-down portion 242 for pressingdown the hopper. A bearing portion 243 formed between separation pawl241 and pressing-down portion 242 is attached to a support shaft 223bformed in the above-described right-side holder 223, and is swingablysupported about support shaft 223b. In FIGS. 8(a) to 8(c), a tongue 224serves as a stopper for preventing bearing portion 243 from coming offsupport shaft 223b after bearing portion 243 is fitted to support shaft223b.

Swinging member 240 has a receiving portion 245 which abuts against anactuating portion 261 of operation lever 260. Formed in a rear portionof receiving portion 245 is a holding portion 245a for holding therotated position of operation lever 260, that is, actuating portion 261,when operation lever 260 is rotated (see FIG. 12).

As shown in FIG. 6, swinging member 250 is arranged substantiallysymmetrical with swinging member 240 and is similarly constructed. Thus,as shown in FIG. 6, swinging member 250 includes pressing-down portions252 and 253 and a bearing portion 253, which is attached to supportshaft 225b formed in left-side housing 225. Also, as shown in FIG. 6,swinging member 250 includes a receiving portion 255, having a holdingportion 255a.

As shown in FIGS. 4 and 6, swinging member 240 and 250 are urged in acounterclockwise direction as viewed in FIG. 4 by means of tensilesprings 246, 256, respectively, provided between swinging members 240,250 and lower case 11.

As shown in FIGS. 4, 6 and 9(a) to 9(c), operation lever 260 includesactuating portion 261, 261 capable of pressing down pressing-downportions 242, 252 of swinging members 240, 250. Operation lever 260 isrotatably supported above stacker section 220. In FIGS. 9(a) to 9(c),operation lever 260 is rotatably supported, as bearing portions 262, 262are fitted to shafts 227, 227. Shafts 227 are formed integrally withlower case 11 (see FIGS. 5 and 6). Further, a restricting portion 263restricts the number of sheets of paper P inserted by being inserted instacker section 220 when operation lever 260 is rotated causing swingingmembers 240, 250 to swing by means of the actuating member 261, as shownin FIGS. 12 and 13.

As shown in FIGS. 10 and 11, paper feed-in roller 312, is the onlyfeed-in roller supported on the central portion of a shaft 371. Bearings372 and 373 are respectively supported by bearing supports 229a, 229bwhich are formed integrally with bottom 221 of the case. A gear 374 isfixed to shaft 371. As gear 374 is rotationally driven by a drivingsystem, which will be described later, feed-in roller 312 rotates. Atemporary positioning hole 229c is utilized when a feed-in rollerassembly including feed-in roller 312, shaft 371, bearings 372, 373, andgear 374 is set in lower case 11. The feed-in roller assembly is securedby bearing supports 229a, 229b clamping bearings 372, 373 by means ofside frames which will be described later.

Next, a description will be given of the operation of automatic paperfeeder 210. It should be noted swinging member 250 operates in the sameway as swinging member 240, and therefore a description of the operationof swinging member 250 will be omitted.

FIG. 12 shows operation lever 260 rotated to its position when the paperis to be loaded into the stacker section. Actuating portion 261 ofoperation lever 260 abuts against and presses receiving portion 245 ofswinging member 240 downward. When receiving portion 245 is presseddownward, pressing-down portion 242 moves downward and abuts againstreceiving portion 232 of hopper 230, thereby pressing down hopper 230against the spring force of a compression spring 233. At the same time,as swinging member 240 rotates, separation pawl 241 moves upward. Whenoperation lever 260 rotates in the counterclockwise direction as viewedin FIG. 12, actuating portion 261 engages holding portion 245a,resulting in the rotation of operation lever 260 to the positionillustrated in FIG. 12.

Referring to FIG. 13, if a plurality of sheets of paper is inserted intostacker section 220, the leading edges of a group of excess sheets ofpaper P3 abut against restricting portion 263 of operation lever 260,and their insertion is prevented. Therefore, with restricting portion263 acting in conjunction with separation pawl 241, only an appropriatenumber of sheets of paper P4 is inserted into the stacker section 220.There is no paper that can slide over separation pawl 241.

Specifically, if operation lever 260 rotates, hopper 230 is presseddownward, and separation pawl 241 moves upward. Hence, paper P which isset in stacker section 220 is prevented from entering above separationpawl 241, thereby making it possible to obtain an accurate paperfeeding-in operation. Also, the mechanism for pressing down hopper 230and moving separation pawl 241 upward can be obtained simply by usingswinging member 240 and operation lever 260 in conjunction with oneanother.

Additionally, when operation lever 260 is rotated, since the number ofsheets inserted in stacker section 220 is restricted by restrictingportion 263, the sheets of paper P can be prevented more reliably fromentering above separation pawl 241.

Further, since operation lever 260 also serves as the discharged-papertray, the number of components used is further reduced.

Furthermore, when operation lever 260 is rotated causing actuatingportion 261 to swing swinging member 240, holding portion 245a ofswinging member 240 engages actuating portion 261 to maintain theposition of rotation of operation lever 260. Hence, the operation ofinserting the paper is facilitated.

Subsequently, the group of excess sheets of paper P3 is removed.Operation lever 260 is returned to its original position, as shown inFIG. 3A, and, since there is no pressing down of pressing-down portion242 of swinging member 240, hopper 230 moves upward by the force ofcompression spring 233, allowing the paper to be pressed against feed-inroller 312. At the same time, swinging member 240 returns to itsoriginal position, and separation pawl 241, located above a corner of aleading end of the paper, encloses the corner of the paper, urging thepaper downward.

The operation of the printer in this configuration can now be describedwith reference to FIGS. 14-16. Corner Pd of the leading end of paper Pfed by the rotation of feed-in roller 312 abuts against separation pawl241, thereby forming a loop Pb. The size of loop Pb is restricted byloop holder 233a. If the size of loop Pb reaches a predetermined limit,corner Pd of the leading end of the paper is snapped off and removedfrom separation pawl 241, as shown in FIG. 15. Corner Pd the contactsloop canceling wall 228, eliminating loop Pb. Thus, the sheets of paperP are separated, and individually (FIG. 16) fed to automatic feedingpath 202 (see FIG. 3A). When feed-in roller 312 is rotating, deskewingis performed as more particularly described below as the leading edge ofpaper P fed in is pressed into each nip between gate roller 340 andpaper feed roller 330, which at this time are rotating in a directionopposite to the paper feeding direction. During this period, paper P ispivoted to its plane about a portion of feed-in roller 312 (in thedirections of double-headed arrows X in FIGS. 6 and 17). Subsequently,when feed rollers 330 rotate in the paper feeding direction, paper P iswound around paper feed rollers 330 and reaches print area PA via pinchrollers 350. Print area PA is formed between an upper surface ofintermediate frame 110 and ink jet head H mounted on carriage 60.Carriage 60 reciprocates in a direction perpendicular to the plane ofthe drawing of FIG. 3A. The paper printed on in print area PA passesthrough transport section 380 and discharge section 490 and isdischarged onto operation lever 260 serving as the discharged-papertray. The discharged paper is designated by P1.

Accordingly, a printer constructed and arranged similar to thatdescribed above is more compact than conventional printers since thebottom of stacker session 220 of automatic paper feeder 210 is formed bybottom 221 of the printer case. In this way, any dead space iseliminated between the bottom of the printer case and the stackersection.

In addition, since loop holder 223a and loop canceling wall 228 areformed integrally with the printer case, the printer can be made furthercompact, and, if the paper size is fixed, loop holder 225a and loopcanceling wall 225c can also be integral with the printer case and theprinter can be made even more compact.

The mechanism for driving paper feed-in roller 312 will now be describedwith reference to FIGS. 17-22b.

FIG. 17 is a diagram illustrating a developed state of an overalldriving system of the printer, including rollers. Accordingly, thepositional relationships of the respective rollers and the like in thisfigure do not necessarily agree with those of the other figures.

Feed-in roller 312 is rotatively driven by a feed motor M1 via a geartrain G1, a gear 332 fixed to one end of a feed shaft 331, a gear 333fixed to the other end thereof, a sun gear 313, a planetary gear 314serving as a movable gear, as will be described later, and a feed-ingear 374 fixed to a feed-in roller shaft 371 on which feed-in roller 312is mounted. Planetary gear 314 engages with or disengages from feed-ingear 374, and is adapted to engage with a feed-in gear 374 only when thecarriage is located at the feeding-in position.

FIG. 18 is a left-hand side elevational view illustrating a left-sideframe portion located in the printer case. The left end of feed shaft331 and feed-in roller shaft 371 are respectively supported by left-sideframe 130. Further, FIG. 18 depicts an arm 3140 disposed on an outerside of sun gear 313 and rotatably supported by shaft 133, and whichsupports planetary gear 314.

FIGS. 19 and 20 depict a hole 131 for supporting feed shaft 331, a hole132 for supporting feed-in roller shaft 371. In addition, a shaft 133for rotatably supporting sun gear 313 and an arm 3140, which will bedescribed below, is disclosed.

FIGS. 21(a) to 21(g) are diagrams further illustrating arm 3140.

Arm 3140 has a hole 3141 rotatably fitted on shaft 133 of the side frameand a shaft 3142 for rotatably supporting planetary gear 314 (see FIG.18). Reference numeral 3143 denotes a support portion for engaging oneend of spring member 150 (see FIGS. 18, 22a, 22b), which is formed inthe shape of a pin having a slit 3143a.

Referring to FIGS. 21(a)-21(d), a stopper 3144 is formed on arm 3140,and is inserted in a fan-shaped hole 137 (see FIG. 19) formed in sideframe 130. Accordingly, arm 3140 of this embodiment is rotatable withinthe range of hole 137, but arm 3140 is normally held at the positionshown in FIG. 18 since spring member 150 tends to extend straight.

FIGS. 22(a) and 22(b) depict spring member 150 which includes arod-shaped coil spring, and lower end 151 thereof is fitted over thesupport portion 3143 of the arm, as shown in FIG. 18. An upper end 152of spring member 150 is supported and abuts against a projection 135formed in a recess 134 of side frame 130, as shown in FIGS. 18-20. Anintermediate portion 153 of spring member 150 is supported such that twoportions thereof are covered by two holding pieces 136, 136 formed onside frame 130 with a space 138 therebetween. At the normal position ofspring 150, arm 3140 is held in a position such that planetary gear 314does not engage feed-in gear 374.

Reference is now made to FIG. 23 which shows a partially-cutaway planview of carriage 60. Actuating portion 564 is provided on the left-sidesurface of carriage 60. Actuating portion 564, a projection-like member,has a tapered surface 565 formed at a distal end thereof. When carriage60 is brought to the feeding-in position adjacent side frame 130,actuating portion 564 passes through hole 137′ formed in side frame 130and through the space 138 between holding pieces 136, 136, and pressesand displaces intermediate portion 153 of spring member 150 to the rightas viewed in FIG. 18, allowing arm 3140 to rotate so planetary gear 314meshes with feed-in gear 374. Because spring member 150 is a rod-likecoil spring, the force of actuating portion 564 upon spring member 150is effected smoothly (see FIG. 24). Spring member 150 is restricted fromdisplacement in other directions by holding pieces 136, 136.

In addition, the meshing (pressing) action of planetary gear 314 withfeed-in 374 by the rotation of arm 3140 results from actuating portion564 of carriage 60 pressing against spring member 150, and the operationof the meshing of planetary gear 314 with feed-in gear 374 is effectedwith the resiliency of spring member 150. Hence, a smooth meshingoperation is obtained. Furthermore, sun gear 313 rotates so planetarygear 314 meshes with feed-in gear 374 and planetary gear 314 and feed-ingear 374 do not disengage until the force by actuating portion 564 uponintermediate portion 153 of spring member 150 terminates.

Reference is now made to FIG. 25 illustrating a flow chart describingthe operation of the above driving mechanism.

When a paper feed signal is inputted to the printer from anunillustrated host computer or the like, carriage 60 moves to thefeed-in position (step ST1). Upon movement of carriage 60 to the feed-inposition, actuating portion 564 presses and displaces intermediateportion 153 of spring member 150, so that arm 3140 rotates (FIG. 24)allowing planetary gear 314 to engage feed-in gear 374.

In Step ST2, a paper feed counter N (counting the number of stepsdefining the rotary displacement of the feed motor M1) is reset suchthat N=0.

Next, paper feed motor M1 is rotated in reverse (step ST3) and the paperfeed counter begins to count in increments of 1 (Step ST4).

The reverse rotation of feed motor M1 causes feed rollers 330 and gear333 to rotate reversely. As shown in FIG. 24, this rotation istransmitted to feed-in gear 374 via sun gear 313 and planetary gear 314.As a result, feed-in roller 312 rotates in the clockwise direction asviewed in FIG. 24 so that paper P is fed in by the operation of theabove-described automatic paper feeder.

Next, a determination is made on the basis of a signal from paperdetection switch 923 as to whether or not the paper is actually beingfed in (step ST5).

If the paper is being fed in, feed motor M1 is reversely rotated by apredetermined amount (here, by 120 steps) (step ST6).

As a result, the paper is fed further, and deskewing is performed as theleading end of the paper is pressed against each nip between gate roller340 and paper feed roller 330 rotating in a direction opposite to thepaper feeding direction, and the paper is rotated about its portion incontact with feed-in roller 312 (in the directions of double-headedarrow X in FIG. 17).

In Step ST17, carriage 60 is moved to a printing standby position (aposition where actuating portion 564 is disengaged from spring member150).

When actuating portion 564 ceases to press against spring member 150,arm 3140 also returns to its original position (the position shown inFIG. 18) by virtue of the spring action of spring member 150 and thereis no engagement of planetary gear 314 with paper-feed gear 374.

In Step ST8, feed motor M1 is rotated forward by a predetermined amount(here, by 610 steps).

As a result, paper feed rollers 330 rotate in a clockwise direction asviewed in FIG. 24, the paper is wound around paper feed rollers 330, andthe leading end portion of the paper reaches print area PA via pinchroller 350, thereby assuming the so-called “head-out” state.

In Step ST9, the operation waits for a print signal.

Subsequently, when the print signal is inputted, while carriage 60reciprocates by the operation of a carriage motor (not shown), ink isejected from ink jet head H and printing takes place. The printed paperis discharged onto discharged-paper tray 260 via transport section 380which includes transport rollers 381a-381d (FIG. 1) and star wheels382a-382d (FIG. 1), as well as discharge section 490 which includespushing-up portions 491, 491 (FIG. 33) for pushing up both sides of thepaper and a knurled roller 492 for pushing down a central portion ofpaper P1 (FIG. 3A).

As illustrated in step ST5 of FIG. 25, if the paper is not being fed in,a determination is made as to whether or not the number of steps ofreverse rotation of feed motor M1 (the number of steps N counted in StepST4) has reached 1000 (step ST10).

If feed motor M1 has reached 1000 steps, it is determined that there isno paper in automatic paper feeder 210, and in Step ST11, a display isgiven on a display unit (not shown) to the effect that there is “nopaper.”

If N has not reached 1000 steps, Step ST3 and subsequent steps arerepeated.

In accordance with the driving mechanism of this embodiment, sinceintermediate portion 153 of spring member 150 is pressed and displacedby actuating portion 564 of carriage 60, arm 3140 rotates and causesplanetary gear 314, which is a movable gear, to engage feed-in gear 374.Hence, feed-in roller 312 rotates. Also, the operation of the engagementof planetary gear 314 with feed-in gear 374 is performed with theresiliency of spring member 150. Hence, a smooth meshing operation isobtained, and a smooth and reliable rotating operation of feed-in roller312 can be obtained.

Spring member 150 has one end 151 supported by arm 3140 and the otherend 152 supported by side frame 130. When the pressing of actuatingportion 564 of carriage 60 against spring member 150 ceases, springmember 150 returns to its original state. If the pressing of actuatingportion 564 of the carriage against intermediate portion 153 of springmember 150 ceases, arm 3140 also returns to its original position byvirtue of the returning action of spring member 150. As a result, theengagement of planetary gear 314 with feed-in gear 374 ceases.

Thus, spring member 150 serves to rotate arm 3140 and also serves toreturn arm 3140 to its original position.

It is understood that various modifications can be made to the actuatingmechanism and driving mechanism.

For example, the actuating mechanism is not limited to the spring memberdisclosed above. It is possible to use a mechanism and rotate anordinary lever L, as shown in FIG. 26. In FIG. 26, a lever L isrotatably supported by a shaft L1. In this embodiment, by pressing aspring member S by an actuating member A, lever L will rotate.

The spring member also need not be a rod-like coil spring, and, in itsplace, a leaf spring may be used. In this case, a smooth operation canbe obtained if portions of contact between the leaf spring and theactuating portion are shaped to contact each other smoothly. However,when the spring member is formed of a rod-like coil spring 150, a smoothoperation can be obtained without needing to provide such shaping.

Furthermore, in the driving mechanism disclosed above, the movable gearneed not be a planetary gear. It suffices if the movable gear assumes atleast two positions, one, a position where it engages the feed-in gearby the rotation of the arm to rotate the feed-in gear, and a positionwhere it does not engage the feed-in gear.

Next, a description will be given of print area PA.

Referring back to FIG. 3A, print area PA is formed between an uppersurface of ink shielding portion 112 and ink jet head H attached tocarriage 60 which reciprocates in a direction perpendicular to the planeof the drawing.

Ink shielding portion 112 is formed integrally with intermediate frame110, and is arranged over the entire print area PA with extends in adirection perpendicular to the plane of the drawing of FIG. 3A. FIGS. 28and 30 depict rib-shaped paper guides 113 that are formed on the uppersurface of the ink shield portion 112 downstream of a portion 112aopposing the print area.

As shown in FIGS. 27 and 31, pressing member 140 is formed in the shapeof a thin plate, and is attached to the underside of a lower end of rearframe 130. The distal end of pressing member 140 extends linearly in adirection perpendicular to the plane of each of these drawings, andincludes a pressing portion 141 for pressing paper P over the entirewidth thereof. Pressing portion 141 is disposed at a position betweenfeed rollers 330 and transport rollers 381. Pressing portion 141 doesnot contact either of the two rollers 330 or 381. As shown in FIG. 27,the distal end of pressing portion 141 is located at a slightly lowerposition from a tangent T to both feed roller 330 and transport roller381, and is arranged to press paper P downward.

For this reason, the paper is guided slightly downward when the paper isfed by feed rollers 330 and the leading end of the paper enters printarea PA. However, the position of pressing portion 141 is set such thata leading end Pa′ (dotted-dash line in FIG. 31) of the paper passesabove portion 112a, opposing the print area, of ink shielding portion112 without coming into contact with portion 112a, and is brought intocontact with paper guides 113.

Next, a description will be given of the printing operation in theabove-described print area.

The paper fed to automatic feeding path 202 by the operation ofautomatic paper feeder 310 is detected by paper detection switch 923.The detected paper is subjected to deskewing, and is then wound aroundfeed rollers 330, and its leading edge enters print area PA.

After the paper is detected by detection switch 923, the paper may failto reach print area PA due to a failure in paper feed or the like.However, even if the ink is ejected blindly by ink jet head H the inkwill strike ink shield portion 112, so that the ink does not adhere tofeed roller 330 or damage any other components.

In addition, as shown in FIG. 32, since the paper set in automatic paperfeeder 210 is located below ink shield 112, this paper does not becomestained.

Furthermore, as noted above, leading edge Pa′ of the paper thatsubsequently enters print area PA is guide so that it passes aboveportion 112a, opposing the print area, of ink shielding portion 112without contacting portion 112a, and abuts against paper guides 113, asshown in FIG. 31. Therefore, the paper is not stained by any ink thatmay be adhering to ink shielding portion 112.

The leading edge of the paper which has entered printed area PA isreliably guided to paper discharge rollers 381 by paper guides 113, andprinting is performed in a state in which the paper floats in the air bybeing pulled by transport rollers 381 and star wheels 382, as shown inFIG. 31.

Paper P is pressed over its entire width by pressing portion 141 so asto position the printing surface. Pressing portion 141 is not affectedby the processing accuracy of the surface of feed rollers 330, andmaintains a gap G between the printing surface of paper P and ink jethead H constant. In this embodiment, and as illustrated in FIG. 17, onlythree feed rollers 330 are provided as set intervals. Even in such acase, gap G remains constant between the printing surface of paper P andink jet head H.

FIG. 33 shows the paper printed in print area PA being discharged ontodischarged-paper tray 260 via transport section 380 and dischargesection 90.

FIG. 1 depicts transport section 380, which includes six paper dischargerollers 381 (specifically, 381a to 381f) formed of a resilient material,such as rubber, and six star wheels 382 (specifically, 382a to 382f)disposed in face-to-face relation with paper discharge rollers 381a to381f, respectively.

Paper discharge rollers 381 are fixed in units of three rollers to tworotating shafts 383 and 384, respectively, which are supported byintermediate frame 110. As shown in FIG. 17, paper discharge rollers 381are rotated as gears 383a, 384a fixed to rotating shafts 383, 384 arerotatably driven by left and right feed rollers 330 via two transmittinggear, generally indicated at 385.

Transmitting gear 385 is constructed and arranged so that a gear portion385a (meshing with either gear 383a or 384a fixed to rotating shaft 383or 384, respectively), a roller portion 385b held in rolling contactwith feed roller 330 and a common shaft 385c are integrally formed. Bothends of common shaft 385c are movably supported in rectangular holes 111formed in intermediate frame 110, as shown in FIGS. 27 and 28. In thisconfiguration, transmitting gear 385 acts as a one-way clutch. That is,as shown in FIG. 27, when each feed roller 330 rotates in the paperfeeding direction, transmitting gear 385 moves downward (in the engagingdirection) along rectangular holes 111, and transmits the power of eachfeed roller 330 to three paper discharge rollers 381. FIG. 28illustrates that if feed roller 330 rotates in a direction opposite tothe paper feeding direction, transmitting gear 385 moves upward (in theescaping direction) along rectangular holes 111, and does not transmitthe power of feed rollers 330 to paper discharge rollers 381.Accordingly, paper discharge rollers 381 rotate only when feed rollers330 rotate in the paper feeding direction, and they do not rotate whenfeed rollers 330 rotates in the reverse direction.

In FIGS. 1 and 17, star wheels 382 are fixed in units of two star wheelsat opposite ends of three shafts 386, respectively. Opposite ends 386aof the shaft 386 are supported on upper frame 120 (FIGS. 29 and 30).Referring further to FIGS. 29 and 30, a support portion 121 is formed bybending a portion of upper frame 120 downward. Opposite ends 386a ofshaft 386 are supported in elongated holes 122 respectively formed insupport portions 121, and can move in a vertical direction. A spring 387constituting an urging member is fixed over a tongue 123 of upper frame120. One end 387a of spring 387 is engaged with frame 120, while theother end 387b thereof is engaged with a central portion 386b (see FIG.17) of the aforementioned shaft 386, thereby urging the set of two starwheels 382 toward paper discharge rollers 381. Thus, since the centralportion of shank 386 is urged toward paper discharge rollers 381 byspring 387, even if there are variations in the urging forces of springs387, these variations in force applied are distributed to the respectivetwo star wheels 382 via shafts 386, so that the variations of thepressing force of each star wheel 382 against each paper dischargeroller 381 is rotated in half. In this embodiment, the force applied byshaft 386 by means of spring 387 is set to 40 g. Therefore, the force ofeach star wheel against each paper discharge roller 381 is 20 g.

Star wheels 382 rotate by being driven by paper discharge rollers 381,and when transporting the paper, star wheels 382 rotate by nipping thepaper between them and paper discharge rollers 381.

The diameter or the number of teeth of each feed rollers 330,transmitting gear 385, and paper discharge rollers 381 is set so thatthe peripheral speed of paper discharge roller 381 is approximately 12%faster than the peripheral aspect of feed roller 330. Therefore, asdepicted in FIG. 31, paper P is printed upon while in print area PAwhile the paper floats in the air by being pulled by transport rollers381 and star wheels 382.

In FIGS. 1 and 3, discharge section 490 includes supporting portions491, 491. Supporting portions 491, 491 support, from below, both sidesof the paper which has been printed upon in print area PA and is nowbeing discharged. Discharge section 490 also includes pushing-downportion 492 for pushing down a central portion of the paper.

Supporting portions 491 and 491 are defined by fixed ribs formedintegrally with intermediate frame 110. As shown in FIG. 1, supportingportions 491, 491 are disposed at positions aligned with star wheels382a and 382f, respectively, located on opposite sides of theaforementioned star wheels 382, as viewed in the direction of travel ofthe paper. FIG. 31 illustrates that an upper surface 491a of eachsupporting portion 491, 491 is inclined in the discharging direction ofthe paper.

Pushing-down portion 492 is defined by a knurled roller, and isrotatably supported on an arm 493 rotatably attached on upper frame 120.As shown in FIG. 32, arm 493 is in the shape of bifurcated portions493a, 493a, and first stoppers 493b, 493b are formed on distal endsthereof in such a manner as to project therefrom. In addition, secondstoppers 493c, 493c are formed in slightly spaced-apart relation withthe respective first stoppers. A rectangular hole 123 (see FIG. 31) isprovided at a bent portion of upper frame 120. First stoppers 493b, 493bare inserted into this rectangular hole 123 by reducing the distancebetween bifurcated portions 493a, 493a and subsequently increasing thedistance between bifurcated portions 493a, 493a thereby securing arm 493in upper frame 120. With discharge section 490 secured to upper frame120, upper frame 120 is sandwiched by first stoppers 493b and secondstoppers 493c with gaps that do not hinder the rotation of the arm, nordoes arm 493 come off rectangular hole 123.

A description will now be given of the paper discharging operation inthe above-described discharge section.

In FIG. 31, paper P printed in print area PA is transported by beingnipped and pulled by paper discharge rollers 381 and star wheels 382.Since the central portion of each shaft 386 of the star wheels is urgedtoward paper discharge rollers 381 by spring 387, even if there arevariations in the urging forces of springs 387, these variations aredistributed to the respective two star wheels 382 via shafts 386. Hence,the variations of the force applied by each star wheel 382 against eachpaper discharge rollers 381 are reduced by half.

Accordingly, the pressing forces of star wheels 382 against paperdischarge rollers 381 (and ultimately the force upon paper P) arestabilized and proportionately reduced, resulting in paper P beingtransported reliably without any smearing thereon. Moreover, before theleading edge of the paper enters discharging section 490, pushing-downportion 492 is located below upper surfaces 491a of supporting portions491, 491.

When leading edge Pa′ of the paper enters discharging section 490, bothside portions of leading edge Pa are guided gradually upward by uppersurfaces 491a of both-side supporting portions 491. At the same time, acentral portion Pa1 of leading edge Pa gradually pushes up pushing-downportion 492 while rotating arm 493, counterclockwise, but centralportion Pa1 of leading edge Pa then gradually falls below pushing-downportion 492 and is pushed down in comparison with the both side portionsdue to the weight of pushing-down portion 492 and 493 upon centralportion Pa1.

Thus, paper P is discharged, starting with its leading edge, while beingforcibly urged into a concave shape in which the printed surface isconcaved as seen in the discharging direction. Since pushing-downportion 492 is supported by rotatable arm 493, paper P enters belowpushing-down portion 492 smoothly because of the rotating motion of arm493 when the leading edge of paper P is brought into contact withpushing-down portion 492.

FIG. 33 shows paper P discharged up to the midway position.

FIG. 34 depicts paper P forcibly urged into a concave shape and beingdischarged in the discharging direction. Paper P, in this convexconfiguration, can be discharged further in a direction indicated byarrow Z before the weight of the paper itself forces the leading edge tofall, thereby contacting printed surface P1f of paper P1. Paper Pappears to be stiff, and appears to discharge as if it was floating.Because the time until discharged paper P slidably contacts a printedsurface P1f of stacked paper P1 is delayed, the time for the ink on theprinted paper P1 to dry is increased and the risk of any ink smearing onsurface P1f decreases.

FIG. 33 shows transport section 380, and that paper P is transported ina flat state as seen in the discharging direction prior to contactingdischarge section 490. Therefore, when paper P is in the print area PAand shortly thereafter, paper P is flat. Accordingly, satisfactory printquality is ensured.

FIG. 35 shows paper P, after being further transported and having itstrailing edge Pb pass transport section 380, loses its transportingforce. A rear end portion PC of paper P is maintained in its concavestate by discharge section 490. When a subsequent sheet of paper P2enters transport section 380, its leading edge P2a passes transportsection 380. When leading edge P2a contacts trailing edge Pb of apreceding paper P, discharge section 490 does not press againstpreceding paper P as illustrated in FIG. 36. The force applied bydischarging section 490 against preceding paper P ceases by the time itcontacts subsequent paper P2. Preceding paper P is stacked on theearlier printed paper P1 (FIG. 34), and therefore the time until paperP2 contacts printed paper P1 is further delayed.

FIG. 36 shows the point in time when the holding of paper P by dischargesection 490 ceases. After the leading edge P2a of subsequent paper P2contacts trailing edge Pb of preceding paper P, the support of precedingpaper P ceases and the transport of subsequent paper P2 is temporarilystopped. This stopping operation can be performed by determining thenumber of pulses of feed motor M1 is in advance, and stopping thedriving of motor M1 when the number of pulses reaches a predeterminednumber.

If preceding paper P is pushed out by bringing the leading edge P2a ofsubsequent paper P2 into contact with the trailing edge Pb of precedingpaper P, the stacking operation of preceding paper P on earlier printedpaper P1 will be unreliable (see FIG. 34). However, by temporarilystopping the transport of subsequent paper P2, any contact betweenleading edge P2a of the subsequent sheets of paper and trailing edge Pbof the preceding paper is eliminated by making use of the inertia ofpreceding paper P1. In this way, the operation of stacking precedingpaper P on the earlier printed paper P1 becomes very reliable.

Ink jet printers constructed and arranged in accordance with the presentinvention have any fluctuation in the pressing forces of each star wheel382 against each paper discharge roller 381 reduced in half. The centralportion of each shaft 386 has two star wheels 382 at opposite endsthereof. When the star wheels 386 are urged toward paper dischargerollers 381 by spring 387, even if there are variations in the urgingforces of springs 387, these variations are distributed to therespective two star wheels 382 via shafts 386.

Accordingly, the pressing forces of the star wheels 382 upon paperdischarge rollers 381, and, therefore, upon paper P are stabilized andproportionately reduced, resulting in the discharge of paper withoutdamaging the printing surface.

In addition, the paper is discharged in a floating state because theprinted paper is discharged while forced into a concave shape in whichthe printed surface is concave as seen in the discharging direction.And, if the paper discharged is very stiff, it also will not slidablycontact with the printed paper since the stiff paper will remain in theair longer making it possible to prevent the printed surface of theprinted paper from becoming smeared.

Postcards and envelopes, for example, have very small widths and maycontact only one pushing-up portion 491. Therefore, the concave shapemay not be formed. However, because of their inherent stiffness, theywill not bend when held in a cantilever fashion and will remain in theair a sufficient time even though only one pushing-up portion 491 may beacting upon the postcards or envelopes.

The above construction and arrangement yield many advantages.

First, the discharged-paper tray for stacking the printed sheets ofpaper does not need to be formed in a concave shape, it is possible toreduce the space occupied by the discharged-paper tray.

Second, since the cancellation of the holding of the preceding paper,i.e., the final discharging operation, is effected by the ensuing paper,it is possible to make unnecessary the transporting/driving means forthe preceding paper in the holding section for holding the paper in aconcave shape.

Third, since the supporting portions are formed by fixed ribs, and thepushing-down portion is a knurled roller, the paper can be forciblyurged into a concave shape with a simple arrangements. Moreover, sincethe knurled roller is brought into contact with the printed surface, theprinted surface is prevented from becoming stained.

Fourth, since the upper surfaces of the fixed ribs are inclined upwardin correspondence with the paper discharging direction, the placing ofthe paper into a concave shape can be made smooth. Since the knurledroller is supported by the rotatable arm, the changing motion of thepaper into a concave shape is effected more smoothly in conjunction withthe aforementioned rotating motion.

Fifth, since th weight of the knurled roller forces the paper downward,an urging means such as a spring becomes unncessary, and the paper canbe forcibly urged into a concave shape with at least one less component,resulting in a much simpler construction.

Next, a description will be given of the construction and arrangement ofink cartridge 90 which is mounted on carriage 60.

FIG. 23 is a plan view illustrating carriage 60. Carriage 60 includes acarriage body 62 and a carriage cover 63, with ink cartridge 90 mountedthereon. FIG. 37 is a plan view, with certain parts omitted, of carriage60 with ink carriage 90 not mounted thereon.

A head surface 71, to which head H is fixed in advance, is incorporatedin carriage body 62. A connecting portion 75 for connection with inkcartridge 90 is formed integrally with head substrate 71. A connectingportion, generally indicated at 75, is formed in a hollow cylindershape, and a needle 75a for breaking the seal of the ink cartridge isformed in a central portion thereof. An ink channel 75c, connected to anink channel 70b in head H, are both formed in a central portion ofneedle 75a.

Carriage cover 63 includes pins 63b, 63b that fit in round holes 62b,62b placed in the corners on a lower side of carriage body 62. A pair ofclaws 63a, 63a engage with square holes 62a, 62a (FIG. 38) formed inside walls of carriage body 62. Carriage cover 63 is secured to carriagebody 62 by placing pins 63b in round holes 62b, and by the engagement ofclaws 63a with square holes 62a.

A mounting portion 64 is formed in a box shape and integral withcarriage cover 64. Ink cartridge 90 is mounted on mounting portion 64.Connecting portion 75 of the head substrate is fitted in an elongatedhole 65. Slits 67, having relatively large widths, are formed in leftand right side walls of mounting portion 64 and serve as paths for pins94 of the ink cartridge. (See FIGS. 23 and 39). Supporting portions 66are formed on the upper surface of the carriage cover 63.

As shown in FIG. 39, ink cartridge 90 has, in its bottom, a connectingportion, generally indicated at 91, for engagement with head substrate71. Connecting portion 91 engages connecting portion 75 of headsubstrate 71 when ink cartridge 90 is mounted in mounting portion 64.Essentially simultaneously, needle 75a breaks a seal 92 of connectingportion 91. When seal 92 is broken, ink is supplied to a nozzle 70a ofthe head through ink channel 70b and ink channel 75c.

As shown in FIGS. 23 and 39, semispherical convex portions 93 and pins94 are formed integrally with both side surfaces of ink cartridge 90.

FIGS. 39-41 depict a lever, generally indicated at 80, which is used tomount or demount ink cartridge 90 on carriage 60. Lever 80 includes atab 81 and a pair of arms 82, 82. Arms 82, 82 are formed integrally withtab 81. Shafts 83, 83 are formed integrally on the outer sides of arms82. Shafts 83, 83 are rotatably supported by supporting portions 66 solever 80 is rotatably supported in the directions of arrows a1 and a2 inFIG. 39.

A cam groove, generally indicated at 84, is formed on the inner side ofeach arm 82. Cam groove 84 includes an introducing groove 84a thatintroduces pin 94 of the cartridge into cam groove 84. Cam groove 84 hasthree sections in addition to 84a. These sections are starting portion84b, curved groove 84c and terminating portions 84d. Starting portion84b communicates with introducing groove 84a. Terminating portion 84dcommunicates with the starting portion 84b via a curved groove 84c.Using shaft 83 as a center, radius R (FIG. 41) gradually increases asradius R moves from starting portion 84b to curved groove 84c toterminating portion 84d. FIG. 40 clearly shows portions 84b, 84d, andcurved groove 84c as a continuous slot that extends through the surfaceof each arm 82. Introducing groove 84a does not extend through arm 82.

A tongue 85 is a resilient member. Tongue 85 is formed integrally in arm82 by means of a U-shaped slit 86. An elongated hole 85a is formed at adistal end of tongue 85.

As shown in FIGS. 23 and 39, with ink cartridge 90 mounted, tongues 875and 85 can flex, and semispherical convex portions 95 engages inelongated holes 85a, respectively, allowing tongues 85 to resilientlyhold the upper portion of ink cartridge 90 in the direction of movementof the carriage is indicated by arrows A and B in FIG. 23.

A stopper pin 87 will contact support portion 66 of carriage cover 63 torestrict any excess rotation of lever 80 when lever 80 rotates in thedirection of arrow a2 (FIG. 40).

FIG. 42 illustrates the mounting and demounting operation of inkcartridge 90 using lever 80.

First, lever 80 is rotated in the direction of arrow a2, and the emptyink cartridge is removed. A new ink cartridge 90 is then placed lightlyinto mounting portion 64 (see FIGS. 23 and 39) from above (this state isshown by the phantom line, and corresponding reference numeralsindicated by adding “′” thereto). Each pin 94′ of the cartridge passesthrough the slit 67 in mounting portion 64, and is then guided by anintroducing groove 84a′ of the cam groove in a lever 80′, and reaches astarting position 84b′ of the cam groove.

Therefore, if lever 80′ rotates in the direction of arrow a1, each pin94′ enters curved groove 84c. Since radius R increases as describedheretofore, pin 94′ is forced downward in slit 67 as lever 80′ rotatesin the clockwise direction. Therefore, a cartridge 90′ is graduallyforced downward. As cartridge 90′ moves downward, a connecting portion91′ of the cartridge connects to connecting portion 75 of the headsubstrate, and a seal 92′ is broken.

When lever 80′ fully rotates in the direction of arrow a1 and reachesthe position indicated by the solid lines (FIG. 42), each pin 94 reachesterminating portion 84d of the cam groove, and the cartridge iscompletely mounted. Moreover, the user is easily able to confirm that acomplete fitting state has been obtained since each convex portion 93 ofthe cartridge is fitted with a click in elongated hole 85a in eachtongue 85 of the lever.

When ink cartridge 90 is empty, ink cartridge 90 can be easily removedsimply by rotating lever 80 in the direction of arrow a2 and lifting upthe cartridge.

FIG. 43 depicts the carriage stop position for performing theabove-described operation.

This carriage stop position serves as a capping position in which a cap100 is fitted to head H. Cap 100 is fitted to head H when the carriageis stopped. Cap 100 prevents the ink from drying in the nozzle of thehead. Cap 100 can also remove any clogging of the ink by sucking the inkfrom the nozzle. A lever 101 moves cap 100 vertically. A pump unit 102performs the sucking operation.

FIGS. 43 and 44 depict an upper case of the printer, generally indicatedat 13, and an upper portion (a portion corresponding to theaforementioned carriage stop position) 13b of its ceiling portion 13a isnotched and an opening is provided, whereby the rotating operation ofthe aforementioned lever 80 is made possible.

A forward end of ceiling portion 13a is formed as a suspended portion13c extending downward, and a right end face 13d thereof is formed as astopper.

Therefore, if lever 80 fully rotates in the direction of arrow a1, i.e.,if ink cartridge 90 is completely mounted in mounting portion 64, lever80 can extend below ceiling portion 13a, and carriage 60 can move in thedirection of arrow z (FIG. 43). However, as illustrated in FIG. 45, iflever 80 is not fully rotated in the clockwise direction, ink cartridge90 will not be fully mounted and lever 80 will abut against stopper 13d.This will hinder the movement of carriage 60. The above-describedconstruction and arrangement has the following advantages.

First, in the event of an incomplete mounting of the ink cartridge, anydamage to the structure by the movement of the carriage will only be tothe lever 80 and not to the ink cartridge itself. This is because thelever will contact the stopper, and the ink cartridge. Specifically,referring to FIG. 45, if the lever 80 is not fully rotated clockwise,ink cartridge 90 will not be fully installed. When carriage 60 moves inthe direction as shown by arrow z (FIG. 43), lever 80 will abut againstthe stopper 13d and the movement of carriage 60 will stop. However,carriage 60 is stopped because lever 80 abuts against stopper 13d, notbecause ink cartridge 90 abuts against stopper 13d. Hence, ink cartridge90 will not be disengaged with carriage 60 and the ink cartridge willnot break.

Second, if the carriage begins to move without the ink cartridge beingfully installed, the lever will very shortly thereafter abut thestopper, preventing any further movement of the carriage. Specificallyreferring to FIG. 45, the carriage stop position is provided formounting or demounting ink cartridge 90 in/on carriage 60. Stopper 13dis placed in the vicinity of this carriage stop position. Therefore, ifcarriage 60 begins to move before lever 80 has been fully rotatedclockwise and ink cartridge 90 is not fully mounted, the lever 80 willabut against stopper 13d, thereby stopping the movement of carriage 60.Accordingly, a partially mounted ink cartridge is prevented 90 fromcoming off carriage 60.

Third, the interior of the printer is prevented from becoming started.The carriage stop position serves as the capping position when cap 100is fitted to head H. If there is an increase in pressure in the inkchannel when ink cartridge 90 is mounted on cartridge 60, the ink iscaptured by cap 100.

Fourth, the stopper construction, specifically stopper 13d, is verysimple. Stopper 13d is integral with case 13 of the printer.

Fifth, the construction and arrangement of tongues 85 aid in reducingthe vibrations, and any ancillary noise due to the vibrations, ofcarriage 60 when carriage 60 reverses direction. Tongues 85 of lever 80resiliently support ink cartridge 90 in carriage 60. When carriage 60moves, the inertial force and vibrations of ink cartridge 90, whencarriage 60 reverses direction, is transmitted to carriage 60 throughthe tongues 85. Therefore, because of the construction of tongues 85,the inertial force of ink cartridge 90 is transmitted to carriage 60 ina dampened state, and any vibrations and noise are reduced.

Reference will now be made of the ink jet printer constructed inaccordance with a second embodiment of the present invention.

A major difference between the second embodiment and the firstembodiment is in the carriage and the structure for supporting thecarriage. All other features of the second embodiment are similar inconstruction and arrangement to those of the first embodiment.

FIG. 46 is a schematic diagram illustrating the print area and thenonprint area in this second embodiment, with a print area PA, and anonprint area A1 and A2 located on both sides of the print area PA. Aframe F is also shown.

In this embodiment, the carriage selectively effect the paper feedingoperation or the suction operation by being first allowed to enter firstnonprint area A1 to select the state of a changeover means provided onthe carriage. Then the carriage enters second nonprint area A2 to changeover the position of a drive gear by using the changeover means.

Referring to FIG. 48, a carriage 610 will reciprocate in the directionof arrows z and y while guided by a rod 619 (see FIG. 51) and an upperend F1 of frame F. FIG. 49 shows a bearing 611 for rod 619 and anengaging portion 612 for engagement with upper end F1 of the frame.Engaging portion 612 is constructed and arranged to loosely mount andslide along upper end F1 of frame F.

An ink jet head H is mounted on carriage 610, and printing takes placeby injecting ink i toward a sheet of recording paper (not shown) locatedbelow head H, as shown in FIG. 49.

In FIGS. 47 and 49, a drive gear, generally indicated at 20, isconnected to a rotating shaft 21 slidably supported by frame F. Drivegear 20 achieves a paper-feed driving position for driving a paperfeeding mechanism (see FIG. 17) by engaging a paper-feeding-mechanismdriving gear 22. Drive gear 20 can also achieve a suction drivingposition for driving a suction mechanism which includes pump unit 102(see FIG. 43) and the like, by engaging a suction-mechanism driving gear23. A flange 24 is rotatably attached to a rotating shaft 21, and acompression spring 25 is interposed between flange 24 and the frame.Driving gear 20 normally engages the paper-feeding-mechanism drivinggear 22 because compressing spring 25 forces rotating shaft 21 in thedirection indicated by arrow z as shown in FIG. 48.

An actuating piece, generally indicated at 30, is formed of a resilientmember (e.g. a leaf spring), and includes a proximal portion 31rotatably supported on the frame by a shaft 31a. As shown in FIG. 49,actuating piece 30 has a ring portion 32 with a hole 33 formed therein.A small-diameter portion 20a of drive gear 20 is loosely fitted in hole33. The diameter of hole 33 is smaller than an intermediate-diameterportion 20b of the drive gear 20. As shown in FIG. 51, a distal end ofactuating piece 30 is formed in a substantially L-shaped configurationand has a projection 34 located in a rear portion of carriage 610.

Referring primarily to FIGS. 48 and 51, a changeover lever, generallyindicated at 40, serves as the changeover means and is disposed in therear portion of carriage 610 in such a manner as to be rotatable on ashaft 613. Changeover lever 40 is formed of a synthetic resin, andincludes a boss 41 attached to shaft 613, an actuating lever 42 formedintegrally with boss 41, and a locking lever 43 also formed integrallywith boss 41. Locking lever 43 sets the rotation of the actuating lever42.

Actuating lever 42 has a substantially Y-shaped configuration andincludes first and second distal end portions 42a, 42b.

As shown in FIG. 54, a retainer 43a and a resetting projection 43b areformed integrally with a distal end of locking lever 43. Retainer 43a isformed by being bent substantially orthogonally toward the carriage andwhose distal end is formed as an inclined surface 43c. Retainer 43aengages a capping-position hole 614 or a suction-position hole 615formed in carriage 610. As shown in FIG. 55, when resetting projection43b is engaged with suction-position hole 615, resetting projection 43bis capable of engaging a resetting protrusion F3 which is formed bybeing bent downward from a top portion F2 (see FIG. 49).

In FIG. 54, a spring 44 is disposed between changeover lever 40 andcarriage 610. Spring 44 is constantly forcing changeover lever 40 torotate in the clockwise direction.

In FIGS. 52 to 54, a selecting protrusion F5 serves as a selectingmeans, and is formed by being bent toward this side from a rear portionF4 of the frame. Selecting protrusion F5 is formed at a position capableof abutting against first distal end portion 42a of actuating lever 42when carriage 610 has entered deeply into first nonprint area A1.

Next, a description will be given of the operation of theabove-described mechanism.

Similarly to a conventional printer, the printing operation is performedso that carriage 610 reciprocates across print area A, ink i is ejectedfrom head H, the printing paper is fed for the portion of theinterlinear space each time one line is printed, thereby printing onesheet of recording paper.

While printing on a sheet of paper, carriage 610 shallowly enters fromfirst nonprint area A1, and the feeding-in operation and feedingoperation of a subsequent sheet of recording paper are performed. Atthis time, since carriage 610 only shallowly enters into first nonprintarea A1, the first distal end portion 42a of actuating lever 42 does notabut against selecting protrusion F5, as indicated by the solid lines inFIG. 52. Thereafter, the carriage 610 returns to print area PA, andprinting is performed on the second sheet of recording paper. The sameoperation is repeated until a predetermined number of sheets areprinted.

The capping operation is performed when no print signal is detected fora predetermined period of time. Head H is covered with cap 100 (FIG. 43)to ensure that the ink at the nozzle tip of head H does not dry and thatthe nozzle does not clog.

In this case, carriage 610 enters second nonprint area A2. As shown bythe solid lines in FIG. 48, retainer 43a of locking lever 43 ofchangeover lever 40 is engaged in capping-position hole 614 in thecarriage, so that actuating lever 42 rotates clockwise. For this reason,even if carriage 610 enters second nonprint area A2, second distal endportion 42b of the actuating lever 42 does not abut against projections34 at the tip of the actuating piece, and passes below projection 34, asshown in FIG. 49. Accordingly, actuating piece 30 maintains an uprightstate as indicated by the solid lines in FIG. 48, so that drive gear 20remains engaged with paper-feeding-mechanism driving gear 22.

In this way, the capping operation is performed and drive gear 20 willrotate so the paper feeding operation is performed.

Subsequently, when a print signal is detected, the carriage returns toprint area PA to perform the passing operation.

When the nozzle of head H becomes clogged, it is necessary to eliminatethe clogging by forcibly sucking the ink from the nozzle by using asuction mechanism. The suction operation is performed by manuallythrowing a switch which may be on the operation panel or the like of theprinter. When the switch is in the ON position, carriage 610 firstenters deeply into the first nonprint area A1. Then, as indicated by thephantom lines in FIG. 52, first distal end portion 42a of actuatinglever 42 contacts selecting protrusion F5, and changeover lever 40rotates counterclockwise against the force of spring 44 (FIG. 54).Inclined surface 43c of retainer 43a at the distal end portion oflocking lever 43 contacts with an upper side 641[a] (see FIG. 48) ofcapping-position hole 614, and retainer 43a disengages fromcapping-position hole 614 while locking lever 43 is deflected in thedirection indicated by arrow a in FIGS. 50 and 54. Selecting protrusionsF5 still forcing changeover lever 40 rotate against the spring force ofspring 44 causes retainer 43a to engage suction-position hole 615. Whenretainer 43a reaches suction-position hole 615, retainer 43a rotates inthe direction of arrow b (FIG. 50) by the resiliency of locking lever43, and engages suction-position hole 615. Changeover lever 40 is nowset in the suction position.

Subsequently, carriage 610 passes print area PA and enters secondnonprint area A2. Then, as indicated by phantom lines in FIG. 48 and 51,second distal end portion 42b of actuating lever 42 contacts projection34 at the tip of actuating piece, thereby flexing actuating piece 30clockwise (in FIG. 48). As actuating piece 30 flexes, ring portion 32 ofactuating piece 30 contacts intermediate-diameter portion 20b of drivegear 20, causing drive gear 20 to slide the direction of arrow y (asindicated by the phantom lines) and engage suction-mechanism drivinggear 23. Furthermore, since actuating piece 30 is resilient (i.e., aleaf spring), the positional variation of carriage 610 is absorbed, anddrive gear 20 engages smoothly with suction-mechanism driving gear 23.

The suction mechanism can now perform the suction operation.

If a print signal is subsequently detected, the carriage returns toprint area PA, and changeover lever 40 is reset in the following manner.When carriage 610 moves in the direction of arrow z (FIG. 48), resettingprojection 43b at the top of locking lever 43 contacts with the rearsurface of resetting protrusion F3, as indicated by the phantom lines inFIG. 49 and a broken-line arrow X1 in FIG. 55. As shown in FIGS. 50 and55, since resetting protrusion F3 is at an angle with respect to theadvancing direction of the carriage, locking lever 43 is detected asindicated at arrow a and retainer 43a disengages from suction-positionhole 615. Then, changeover lever 40 rotates clockwise in FIG. 48 by theaction of spring 44, and retainer 43a enters capping-position hole 614,as indicated by the solid lines of FIG. 48. Resetting projection 43balso abuts against resetting protrusion F3 when carriage 610 enters thesecond nonprint area after changeover lever 40 is set in the suctionposition in first nonprint area A1, in this case resetting projection43b abuts against the front surface of resetting protrusion F3, asindicated by arrow X2 in FIG. 55, and retainer 43a acts in such a manneras to enter deeply into suction-position hole 615. Hence, changeoverlever 40 is prevented from becoming reset.

As described above and in accordance with the ink jet printer of thisembodiment, carriage 610 is first entered into first nonprint area A1 toselect the state of changeover lever 40 provided on the carriage, andcarriage 610 is then entered into second nonprint area A2 to change overthe position of drive gear 20 by means of changeover lever 40. Thus, thepaper feeding operation or the suction operation can be effectedselectively.

Therefore, since the paper feeding operation and the suction operationare selectively performed, the drawback found in conventional mechanismsof the recording paper being fed when the suction operation is performedis eliminated. Furthermore, the drawback of the suction operation beingperformed despite the fact that the head is not clogged is eliminated.Moreover, since only one nonprint area is provided on each side of theprint area, the width of the printer in the direction of the row can bereduced.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in carrying out the above method andin the construction set forth without departing from the spirit andscope of the invention, it is intended that all matter contained in theabove description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

1. An ink jet printer comprising: a printer case having a print areawhere printing upon a sheet is permitted and a nonprint area whereprinting upon a sheet is not permitted, a carriage slideably mounted tosaid printer case so as to slide through said print area and saidnonprint area of said printer case; an ink cartridge mounted on saidcarriage; a lever pivotably attached to said carriage for attaching anddetaching the ink cartridge from said carriage, said lever beingpivotable between an open position where the ink cartridge is detachedfrom the carriage and a closed position where the ink cartridge isattached to the carriage; and a lip attached to said printer case andpositioned above said lever and within said print area for preventingsaid lever from detachment of said ink cartridge when said carriage ispositioned within said print area, and for abutting said lever toprevent said carriage from moving from said nonprint area to said printarea when said lever is in the open position.
 2. The ink jet printer asclaimed in claim 1, wherein said lip extends substantially along thelength of said print area and has a gap formed therein.
 3. The ink jetprinter as claimed in claim 1, wherein said lip is formed integrallywith said printer case.
 4. An ink jet printer comprising: a carriageslideably mounted to said printer case so as to slide along a printarea; substantially U-shaped lever including a first arm having a firstfixed end, a first free end and a first pivot point, a second arm havinga second fixed end, a second free end and a second pivot point, and atab connecting said first fixed end and said second fixed end, saidlever being pivotably mounted to said carriage at said first pivot pointand aid second pivot point for pivoting about a pivoting axis defined asa line drawn between said first pivot point and said second pivot point;and an ink cartridge detachably mounted to said carriage by said lever,wherein, said lever being pivotable about the pivot axis between a firstposition where the lever engages an ink cartridge and a second positionwhere the ink cartridge is attached to the carriage, and, wherein,pivoting of said lever between said first and second positions causesrotation displacement of the ink cartridge relative to said carriage. 5.The ink jet printer as claimed in claim 4, wherein said lever includesat least one resilient member for engaging said carriage when said leveris in the second position.
 6. The ink jet printer as claimed in claim 4,further comprising a head mounted on said carriage having a connectingportion and wherein said carriage includes a mating portion for matinglyengaging said connecting portion when said lever is in the secondposition.
 7. The ink jet printer as claimed in claim 4, furthercomprising a needle attached to said head, and wherein said cartridgehas an ink outlet and includes a seal for sealing said ink outlet, andsaid needle punctures said seal when said lever is in the secondposition to create fluid communication between said cartridge and saidneedle.
 8. The ink jet printer of claim 4, wherein a discernible signalis produced by said lever when said lever is moved to the secondposition thereby signaling that the cartridge is in the attachedposition.
 9. The ink jet printer of claim 4, wherein the pivoting axisis substantially parallel to the direction of the carriage movement. 10.The ink jet printer as claimed in claim 4, wherein said first armincludes a first resilient portion and said second arm includes a secondresilient portion, said cartridge includes a first convex portion and asecond convex portion formed thereon, and said first resilient portionengages said first convex portion and said second resilient portionengages said second convex portion to attach said ink cartridge to saidcarriage.
 11. The ink jet printer as claimed in claim 10, wherein saidfirst resilient portion has a first hole that engages said first convexportion of said ink cartridge and second resilient portion has a secondhole that engages said second convex portion of said ink cartridge whensaid ink cartridge is in the attached position.
 12. The ink jet printeras claimed in claim 4, comprising a first pin and a second pin attachedto said ink cartridge on opposed sides of said cartridge so as toproject outwardly from said sides said first arm having a first camgroove sized and shaped to accommodate said first pin and said secondarm having a second groove sized and shaped to accommodate said secondpin, said first and second cam grooves for guiding said cartridge to anattached position where said cartridge is attached to said carriage. 13.The ink jet printer as claimed in claim 12, wherein each of said firstand second cam grooves has an opening exposed to accept said first andsecond pins when said lever is in the first position, said cam groovebeing shaped to guide said first and second pins and therefore saidcartridge to the attached position when said lever is pivoted from thefirst position to the second position.
 14. The ink jet printer asclaimed in claim 12, wherein said first and second cam grooves each havean inside edge, said first and second cam grooves are shaped relative tosaid pivoting axis so that the distance between the inside edges of thegrooves and said pivoting axis increases as said lever pivots from thefirst position to the second position to displace said cartridge towardsaid carriage to the attached position.
 15. An ink jet printer,comprising: a carriage which moves along a print area; a head mounted onsaid carriage; a U-shaped lever comprising first and second arms and atab joining a first end of each arm, said lever being pivotably mountedon said carriage at a second end of at least one of said arms forpivoting about an axis extending between said second ends of said arms;an ink cartridge mounted on said carriage at least in part by saidlever; and wherein each of said arms includes a resilient portion, saidink cartridge includes convex portions formed thereon, and each of saidresilient portions engage a respective one of each of said convexportions to at least in part support said ink cartridge in said carriagemoving direction.
 16. The ink jet printer as claimed in claim 15,wherein said resilient portions have a hole that engages said convexportions of said ink cartridge when said ink cartridge is in saidcartridge's mounted position.
 17. An ink jet printer, comprising: acarriage which moves along a print area; a head mounted on saidcarriage; a U-shaped lever comprising first and second arms and a tabjoining a first end of each arm, said lever being pivotably mounted onsaid carriage at a second end of at least one of said arms for pivotingabout an axis extending between said second ends of said arms; and atleast one of said arms including a resilient portion for engagement bysaid ink cartridge to support said ink cartridge in said ink cartridgeon said carriage in a direction of movement of said carriage; an inkcartridge mounted on said carriage at least in part by said lever, saidink cartridge being provided with a pair of pins projecting outwardly onopposed sides in said carriage moving direction, and each of said firstand second arms includes a cam groove for receiving said pins forfacilitating the mounting and demounting of the ink cartridge in saidcarriage.
 18. The ink jet printer as claimed in claim 17, wherein eachof said cam grooves has an opening exposed when said lever is in an openposition, said cam grooves being shaped to guide said pins and thereforesaid cartridge to its mounted position when said lever is pivoted fromsaid open position to a closed position.
 19. The ink jet printer asclaimed in claim 18, wherein said cam grooves are shaped relative tosaid axis of pivoting of said lever so that the distance between a pointon the grooves and said axis of pivoting of said lever increases as saidlever pivots from said open to said closed position to displace saidcartridge toward said carriage to said cartridge's mounted position. 20.An ink jet printer, comprising: a carriage which moves along a printarea; a head mounted on said carriage; a U-shaped lever comprising firstand second arms and a tab joining a first end of each arm, said leverbeing pivotably mounted on said carriage at a second end of at least oneof said arms for pivoting about an axis extending between said secondends of said arms; an ink cartridge mounted on said carriage at least inpart by said lever; and at least one of said arms including a resilientportion for engagement by said ink cartridge to support said inkcartridge in said ink cartridge on said carriage in a direction ofmovement of said carriage; said resilient portion assisting in reducingvibration of said carriage when said carriage is moving in said carriagemoving direction.
 21. An ink jet printer, comprising: a printer case; acarriage slideably mounted to said printer case; an ink cartridge havinga first side including a first pin extending outwardly from said fistside, and a second side including a second pin extending outwardly fromsaid second side, said ink cartridge being attached to said carriage;and a lever having a first arm, a second arm, and a tab connecting saidfirst arm to said second arm, said first arm having a first groove sizedto accept the first pin and said second arm having a second groove sizedto accept the second pin when said lever is at a first position.
 22. Theink printer of claim 21, wherein said first pin and said second pin movewithin said first and second grooves, respectively, to position said inkcartridge on said carriage as said lever pivots from the first positionto a second position.
 23. The ink printer of claim 21, wherein thecarriage includes a supporting portion and said lever includes a stopperpin positioned to contact said supporting portion when said lever is inthe first position to prevent said lever from overpivoting.
 24. An inkjet printer for use with an ink jet head having a nose portion throughwhich ink is ejected, comprising: a paper feeding path which guides asheet of printing paper in a direction from a paper feeding side to apaper discharging side; a paper feed roller having a peripheral surfacecoincident with a portion of said paper feeding path; a driving deviceoperatively coupled to said paper feed roller and selectively rotatingsaid paper feed roller; a presser abutting said paper feed roller at acontact position, the contact position being located on said paperfeeding path, so that when said paper feed roller is rotated by saiddriving device the sheet of printing paper is moved along said paperfeeding path; a flat paper guide surface disposed in said paper feedingpath downstream of the contact position; a printing area located betweenthe flat paper guide surface and the ink jet head and corresponding to aregion over which ink can be applied by ejection by the ink jet head;and a plurality of projections disposed on said paper guide surface, atleast some of which said projections being at least in part disposedinside of the printing area which is located between the contactposition where said presser abuts said feed roller and a position wherethe nose portion of the ink jet head opposes said paper guide surfaceacross said paper feeding path when the ink jet head ejects ink, theprojections being arranged at intervals in a direction approximatelytransverse to and beneath said printing paper for supporting the sheetof paper moving along said paper feed path, wherein at least one of saidprojections extends from within the printing area to a point downstreamand outside of the printing area, wherein said paper feeding pathextending at least from the contact position of the presser to theprinting area is substantially flat.
 25. An ink jet printer according toclaim 24, wherein the presser comprises a pinch roller.
 26. An ink jetprinter according to claim 24, further comprising a deflector locateddownstream of and apart from the contact position and which deflects thesheet of paper toward the projections.
 27. An ink jet printer accordingto claim 26, wherein at least one of the presser, the deflector and theplurality of projections extends across a full width of the sheet ofpaper.
 28. An ink jet printer for use with an ink jet head having a noseportion through which ink is ejected, comprising: a paper feeding pathwhich guides a sheet of printing paper in a direction from a paperfeeding side to a paper discharging side; a paper feed roller having aperipheral surface coincident with a portion of said paper feeding path;a driving device operatively coupled to said paper feed roller andselectively rotating said paper feed roller; a presser abutting saidpaper feed roller at a contact position, the contact position beinglocated on said paper feeding path, so that when said paper feed rolleris rotated by said driving device the sheet of printing paper is movedalong said paper feeding path; a flat paper guide surface disposed insaid paper feeding path downstream of the contact position; and aplurality of projections disposed on said paper guide surface, at leastsome of which said projections are at least in part disposed inside ofthe printing area which is located between the contact position wheresaid presser abuts said feed roller and the point where the nose portionof the ink jet head opposes said paper guide surface, the projectionsbeing arranged at intervals in a direction approximately transverse toand beneath said printer paper for supporting the sheet of paper movingalong said paper feeding path, wherein at least one of said projectionsextends from within the printing area to a point downstream and outsideof the printing area, wherein said paper feeding path extending at leastfrom the contact position of the presser to the printing area issubstantially flat.
 29. An ink jet printer according to claim 28,wherein the presser comprises a pinch roller.
 30. An ink jet printeraccording to claim 28, further comprising a deflector located downstreamof and apart from the contact position and which deflects the sheet ofpaper toward the projections.
 31. An ink jet printer according to claim30, wherein at least one of the presser, the deflector and the pluralityof projections extends across a full width of the sheet of paper.
 32. Anink jet printer for use with an ink jet head having a nose portionthrough which ink is ejected, comprising: a paper feeding path whichguides a sheet of printing paper in a direction from a paper source to apaper exhaust; a paper feed roller having a peripheral surfacecoincident with a portion of said paper feeding path; a driving deviceoperatively coupled to said paper feed roller and selectively rotatingsaid paper feed roller; a presser abutting said paper feed roller at acontact position, the contact position being located on said paperfeeding path, so that when said paper feed roller is rotated by saiddriving device the sheet of printing paper is moved toward said paperexhaust; and a flat paper guide surface disposed in said paper feedingpath downstream of the contact position, the flat paper guide surfacehaving a plurality of projections between the contact position and thepaper exhaust beneath said paper feeding path for supporting the sheetof paper moving along said paper feeding path, wherein at least one ofsaid projections extends from within a printing area corresponding to aregion over which ink can be applied by ejection by the ink jet head toa point downstream and outside of the printing area, wherein said paperfeeding path extending at least from the contact position of the presserto the printing area is substantially flat.
 33. An ink jet printeraccording to claim 32, wherein the presser comprises a pinch roller. 34.An ink jet printer according to claim 32, further comprising a deflectorlocated downstream of and apart from the contact position and whichdeflects the sheet of paper toward the projections.
 35. An ink jetprinter according to claim 34, wherein at least one of the presser, thedeflector and the plurality of projections extends across a full widthof the sheet of paper.
 36. An ink jet printer for use with an ink jethead having a nose portion through which ink is ejected, comprising: apaper feeding path which guides a sheet of printing paper in a directionfrom a paper feeding side to a paper discharging side; a paper feedroller having a peripheral surface coincident with a portion of saidpaper feeding path; a driving device operatively coupled to said paperfeed roller and selectively rotating said paper feed roller; a presserabutting said paper feed roller at a contact position, the contactposition being located or said paper feeding path, so that when saidpaper feed roller is rotated by said driving device the sheet ofprinting paper is moved along said paper feeding path; a flat paperguide surface disposed in said paper feeding path downstream of thecontact position; a printing area located between the flat paper guidesurface and the ink jet head and corresponding to a region over whichink can be applied by ejection by the ink jet head; and a plurality ofprojections disposed on said paper guide surface, at least one of whichsaid projections is at least in part disposed within the printing area,said at least one of said projections extending from within the printingarea to a point downstream and outside of the printing area and at leastsome of the projections being arranged at intervals in a directionapproximately transverse to said printing paper and beneath the sheet ofpaper moving along said paper feeding path, wherein said paper feedingpath extending at least from the contact position of the presser to theprinting area is substantially flat.
 37. An ink jet printer for use withan ink jet head having a nose portion through which ink is ejected,comprising: a paper feeding path which guides a sheet of printing paperin a direction from a paper feeding side to a paper discharging side; apaper feed roller having a peripheral surface coincident with a portionof said paper feeding path; a driving device operatively coupled to saidpaper feed roller and selectively rotating said paper feed roller; apresser abutting said paper feed roller at a contact position, thecontact position being located on said paper feeding path, so that whensaid paper feed roller is rotated by said driving device the sheet ofprinting paper is moved along said paper feeding path; a flat paperguide surface disposed in said paper feeding path downstream of thecontact position; and a plurality of projections disposed on said paperguide surface, wherein at least a part of at least one of saidprojection is disposed outside of a region which is defined by thecontact position where said presser abuts said feed roller and a pointwhere the nose portion of the ink jet head opposes said paper guidesurface when the ink jet head ejects ink, at least some of theprojections being arranged at intervals in a direction approximatelytransverse to said printing paper and beneath the sheet of paper movingalong said paper feeding path, wherein at least one of said projectionsextends from within a printing area corresponding to a region over whichink can be applied by ejection by the ink jet head to a point downstreamand outside of the printing area, wherein said paper feeding pathextending at least from the contact position of the presser to theprinting area is substantially flat.
 38. An ink jet printer for use withan ink jet head having a nose portion through which ink is ejected,comprising: a paper feeding path which guides a sheet of printing paperin a direction from a paper source to a paper exhaust; a paper feedroller having a peripheral surface coincident with a portion of saidpaper feeding path; a driving device operatively coupled to said paperfeed roller and selectively rotating said paper feed roller; a presserabutting said paper feed roller at a contact position, the contactposition being located on said paper feeding path, so that when saidpaper feed roller is rotated by said driving device the sheet ofprinting paper is moved toward said paper exhaust; and a flat paperguide surface disposed in said paper feeding path downstream of thecontact position the flat paper guide surface having a plurality ofprojections at least some of which are disposed at least in part betweenthe contact position and the paper exhaust and beneath the sheet ofpaper moving along said paper feeding path, and at least one of saidprojections extends from within a printing area corresponding to aregion over which ink can be applied by ejection by the ink jet head toa point downstream and outside of the printing area, wherein said paperfeeding path extending at least from the contact position of the presserto the printing area is substantially flat.